Polishing machine



. MOULTON.

POLISHING MACHINE.

APPLICATION FILED APILz, Isla.

Patented Apr. 11, 1922.

l 7l il Iql UNITED l STATES LLOYD W. MOULTON, OF SYBACUSE, NEW YORK,

- POLISH'ING MACHINE.

Specification of Letters Patent. Patented Apt 11, 1922.

Application led April 25, 1918. Serial No. 230,672.

To all whom it may concern.' p f Be it known that I, LLOYD W. MOULTON, a citizen of the United States of America, and resident of Syracuse, in the county of Onondaga, in they State of New York, have invented new and useful Improvements in Polishing Machines, of which the following, taken in connection with the accompanying drawings, is a. full, clear, and exact description.

This invention relates to certain improvements in polishing machines'of the handoperated abrasive type adapted to be moved over the surface to be rubbed, ground or polished.

The main object is to provide a comparatively light, compact and easily operable device of this character in which oppositely moving abrasive elements of substantially equal Contact area are driven by an electric motor centrally mounted in the frame of the machine so that the oppositely moving polishing surfaces contacting with the surface to be polished will operate to normally retain the machine in a position of rest during the polishing operation,' while at the same time permitting the machine to be moved to different positions over said surface.

Another object is to support the polishing or 'abrasive members in such manner that the machine may be used for polishing plain, concave or convex surfaces, that is, to make the machine invertible so that either side of the moving, polishing elements nay be applied to the Surface to be polished according to the nature of the contour thereof.

A further object is to utilize the same motor shaft for driving the reversely moving polishing elements `Without clutches or other motion-changing mechanisms.

Other objects relating to specific parts of the machine will be brought out in the following description.

In the drawin Figure 1 is a top plan of a rubbing, polishing or grinding machine embodying the various features of my invention.

Figure 2 is a longitudinal vertical sectional viewl of the same machine taken on line 2 2, Figure l.

Figure 3 is an enlarged horizontal sectional view taken in the plane of line 3 3, Figure 2, the opposite ends of the main supportin frame bein broken away.

As i lustrated, this machine comprises an elongated symmetrical open frame 1 having its transversely slotted cross bars 2 forming handles 3 by which the machine may be moved endwise by hand fromv either end, the central portion of the frame being provlded with an upper transverse bar -1 and lower transverse bars 5- substantially midway between the ends.

l The upper cross bar 4 serves to recelve and support an electric motor 6- which is secured thereto by bolts 7- so that the motor may also be supported substantlally midway between the ends of the frame.

The lower cross bars 5- are spaced a'part longitudinally equal distances from the center of the frame and serve to recelve and support a platen 8 composed of a series of parallel longitudinal bars inl transverse spaced relation to permit the passage between them of the lugs of a series of endless polishing belts, presently described.

The opposite sides of the frame 1 are provided with suitable bearings Q and 9 located equal distances from and at opposite ends of the motor 6 and its supporting bar 4 for receiving and supportrng a pair of parallel cross shafts 10 and 10 which are also located equal distances from and at opposite ends of the` motor 6 at right angles to the armature shaft thereof.

A hollow drum or pulley 11- is secured by suitable keys 12- to the central portion of the cross shaft Q substantially midway between the opposite side Walls of the frame 1 and preferably consists of opposed concavo-convex sections 13 arranged in axially spaced relation with their concave sides facing each other to permit the armature shaft of the motor to pass between them without interfering with their free rotation, the peripheries of the sections 13- being substantially flat to receive one of the abrasive belts, presently described.

A similar hollow pulley or drum 11 is loosely| mounted upon the other cross shaft 10 to permit it to revolve relatively thereto, it being composed of like concave convex sections 13 arranged coaxially in spaced relation to permit the armature shaft of the motor to pass between without interfering with their free rotation, said sections 13 being preferably of the same diameter as the sections 13- and opposite ends provided with Y ,Y is provided at regular intervals throughout its length with inwardly projecting lugs -15- adapted to engage in corresponding apertures -16- in the rim of said pulleys to cause the latter to positively drive the belt in the manner of a sprocket wheel.

Rigidly secured to the shafts l0- and -10- are similar worm gears -17- and -17-, the under sides of which are en' yon opposite ends. of the armature shaft, as

-6-, of the motor -6-, whereby equal' speed motion is transmitted from the motor to both of the cross shafts -10- and -1o. v

A pair of similar, but reversely arranged,

same diameter as that of the drum 11- are loosely `mounted upon the shaft -10- at opposite ends of the pulley .--11- between the last-named pulley and opposite sides of the frame for receiving and supporting the adjacent portions of a pair of endless belts 20-the opposite portions of said belts at the other end of the frame being passed around and supported by a pair of similar pulleys or drums 19'- whicl; are secured by keys -21- to the shaft -10- at opposite ends ofthe central drum or pulley 11-, said drums or pulleys -19- and -19 being of substantially the same diameter as the central 'pulleys 11 and -11 and otherwise are substantially identical with the drums or pulle s n-19,-- except that they are tight on the s aft -10- instead of loose.

The worms -18- and their companion gears -17- and -17- are enclosed in suitable housings or yokes 2Q- in which the adjacent ends of the armature shaft -6- are journaled.

By connecting the several drums or pul.- leys with the Vmotor in the manner just described will cause the belt lllto be driven in one direction, while the belts -20 will bedriven in an opposite direction, the combined width of the belts 20- being substantially equal to the width of the belt '-14'- so that when the active faces or surfaces are brought into contact with the object to be polished,the opposed motions of the contacting faces of the belts will cause the. machine to remain in a normal position of rest upon the object while the belts are movin in contact therewith until the machine 1s shifted by hand to different positions, asl` may be required to operate upon studs -15- adapted to enter apertures 1G- in the rims of their respective drums or pulleys so that positive motion may be transmitted from said pulleys to the belts.

The opposite ends of both of the shafts -10- and -10- are capped by suit-able buffers 23- of rubber or equivalent ma' terial which are held in place by retainers Q4- to protect the object operated upon against injur by contact of adjacent portions of the rame therewith as said frame is moved to different positions uponthe surface of the object.

The platen -8- is disposed in a plane slightly beyond that of the corresponding sides of the drums or pulleys so as to hold the adjacent portion of the belt beyond said plane, or rather to convex that side of the belt longitudinally for operation upon concave surfaces, while the opposite side of the belt is free to flex inwardly to be used in operating upon convex surfaces by simply inverting the machine, the handles -3- -being located in a pla-ne substantially midway betweenopposite sides of the belt.

The central or major'portion of the platen -8- is substantially flat, while its ends are slightly beveled inwardly to allow the belt to travel freely along the outer face of the platen which enables that side of the belt to e used for polishing fiat surfaces.

In operation, the wires leading` to the motor may consist of flexible cables of any suitable length connected to a plug, not

shown, which is adapted to be inserted into any incandescent lamp socket in any wellknown manner, not necessary to herein illustrate -or further describe for supplying current to the motor, whereupon the machine as a whole may be placed upon the surface of the object to be polished and moved back and forth at will until the desired result is attained, the portability and invertibility of the machine as a whole permitting the use of either side of the belt, depending upon the contour of the surface operated upon.

What I claim is :V

1. In a polishing machine, the combination of a frame movable across the surface to be polished, drums mounted on the frame in parallel spaced relation and at opposite sides of the longitudinal center of the frame, additional drums mounted in the frame c0- axial with and between the first named drums, abrasive belts passed around the first named drums, an additional abrasive belt passed aroundv the additional drums, and means for rotating the first named drums and their belts in one direction, and the adin one direction, and the additional drumsV in an opposite direction, the area of contact of the working sides of the abrasive belts moving in reverse directions being substantially equal whereby the machine is permitted to remain in one position while the belts are in action.

3. In a polishing machine, the combination of a frame, an electric motor mounted in the frame and having its armature shaft extending in opposite directions from the motor, cross-shaftsjournaled in the frame at opposite ends of the motor, means actu'- ated by the motor shaft for driving one of the cross-shafts in one direction andthe other cross-shaft in an opposite direction, each cross-shaft having a tight drum and a loose drum thereon, and sepa-rate abrasive belts, each connecting the tight drum of one shaft with the loose drum of the other shaft.

4. In a polishing machine, the combination of a frame, an elect-ric motor mounted in the frame, cross-shafts journaled in the frame at opposite ends of the motor, means actuated by the motor for driving one of the cross-shafts in one direction, additional means actuated by the motor for driving the other cross-shaft in a direction opposite to that of the first'named cross-shaft, adrum secured to one of the cross-shafts to rotate therewith, a separate drum loosely mounted on the other cross-shaft to rotate independently thereof, and an abrasive belt connecting said drums.

5. In a polishing machine, the combination of a frame, an electric motor mounted in the frame, cross-shafts mounted in the frame at opposite ends of the motor, a pair of drums secured to one of the cross-shafts to rotate therewith, a separate vpair of drums loosely mounted upon the cross-shaft to rotate independently thereof, and separate belts connecting the drums of one cross-shaft with those of the other cross-shaft.

6. In a polishing machine, the combination of a frame, an electric motor mounted on the frame, cross-shafts mounted in the frame at opposite ends of the motor, means driven by the motor for rotating one of the cross-shafts in onedirection, additional means driven by the motor for rotating the other cross-shaft in a direction opposite to that of the first named cross-shaft, a pair of drumsl secured to one of the cross-shafts in axially spaced lrelation to rotate therewith, an .additional drum loosely mounted upon the last named cross-shaft between said drums toj'rotate independently thereof,

a separate pair ,of drums loosely mounted upon the-otherl cross-shaft to rotate independently thereof,an intermediate drum secured to ysaid cross shaft between the last named drums, and'separate abrasive belts connecting the tight pulleys on one crossshaft with the loose pulleys on the other cross-shaft.

7. Ina polishing machine, the combination of a frame movable across the surface to be polished. cross-shafts mounted on the frame in parallel spaced relation, each shaft being provided with al tight drum and a loose drum, separate abrasive belts connectingthe tight drum of each cross-shaft with the loose drum on the other cross-shaft, and means for rotating said shafts in opposite directions.

8. In va polishing machine. the combina-- tion of a portable frame movable across the surface to be polished, cross-Shafts mounted on the frame in parallel spaced relation` each shaft being provided with opposite end and intermediate drums, the end drums of one cross-shaft and intermediate drum of vthe other cross-shaft being secured to their H. E. CHASE,

SYBIL IVARNER. 

